While telephone encounters make up nearly 30% of pediatric practice time, quality assessment methods have rarely been applied. In the future, telephone time is likely to increase as pressures to conserve health care resources continue to mount. Prior to increasing our reliance upon any health services delivery method, it is essential to assess its quality. Patient satisfaction, the focus of this project, is one of several important indicators of quality of care. Study objectives were 1) to describe caller satisfaction with after-hours telephone calls, and 2) to determine if various caller/child/physician/call characteristics were associated with satisfaction ratings. The study involved a cross-sectional telephone survey conducted by the PCRU clinincal research staff. Participants were selected (using stratified random sampling) over a seven month period from caretakers calling an after-hours telephone service supported by four inner city, hospital-based primary care clinics. The telephone survey contained questions designed to measure characteristics of the child, caller, and call, as well as caller satisfaction (measured via a 12-item scale developed in a pilot study). Physician characteristics were obtained from the telephone log. Of 1,042 after-hours telephone calls that occurred, 498 were selected for inclusion into the study, and interviews were completed with 322 callers (65%). Out of 100 possible points, the mean (+/- sd) satisfaction summary score was 75 (+/-9). Caller confidence with sick children and caller comfort with the hospital system were associated with higher satisfaction, while first-time parent status, longer waits for call backs, and failure to meet caller expectations for an immediate visit were associated with lower satisfaction (all p<=0.04). Those wishing to improve caller satisfaction with telephone calls and those responsible for educating physicians about telephone medicine should be attentive to waiting time and reamin cognizant of caller characteristics such as confidence with sick children, comfort with the health care system, and parental experience because such characteristics may affect satisfaction ratings.